Exterior doors can be a cause of drafts, air leakage and noise; and a cause of energy waste, through heat flow.
Most exterior doors have a very low insulation value, which is a problem if you are going to build a very energy efficient building.
Wood, steel-polyurethane and Fiberglass Exterior Doors: How Good They Are?Modern exterior wood doors come in a variety of colors and styles, with or without glass panes. Many of them come unfinished.
New premium-grade and heat-treated woods can provide higher dimensional stability to doors, but the insulation value of entry wood doors remains typically low, or very low, even in the case of the best doors.
Most modern exterior steel doors have a steel skin over a polyurethane foam core. Like wood doors, they are available in many styles and sizes and may come with a wood-like coating… Or they can be painted to match the home's exterior.
These doors do no warp, are fire- and crack-resistant, do not swell or shrink, and are very durable and almost without maintenance.
Fiberglass doors can match the insulation of steel doors (many of them also come with a foam insulation core and excellent weatherstripping).
See, for details: Types, prices and features of exterior doors
Choosing a door with good insulation valueIt's not easy to find exterior doors with good insulation.
It's a lot more easier to find doors in the opposite spectrum: cheap metal and plastic doors, that are a major pathway for heat loss and gain.
See, for details: Types, prices and features of exterior doors
Glass Doors Look Nice But Can be a Cause of High Energy CostsGlass patio doors – and other glass doors – are a common cause of huge heat loss in the winter, and unwanted heat gains in hot weather.
See:
Patio & Glass Doors
Door Installation, Glass Panes and WeatherstripsDoor installation should be optimized for insulation and to protect the door and the wall cavities from rainwater. The gap between the door jamb and the rough opening should be carefully flashed and sealed with a proper foam.
Prefer doors with high quality weatherstrips (magnetic weatherstrips are a great choice) for a tighter seal.
If the door has glass panes, make sure that they have a low U-factor (below 0.3, to provide higher insulation resistance) and a low Solar Heat Gains Coefficient, also below 0.3.
Door installation is not a do-it-yourself project.
Installing a prehung door requires the removing of the existing frame, which is an excellent opportunity to seal and insulate the rough opening. That's an important point for energy efficiency, and to prevent water problems.
Weatherstripping your Old Exterior Doors Sealing a door effectively can be a very cost-effective energy improvement project. The goal is, obviously, to prevent drafts and to stop hot air from leaking in or out of the house.
See:
Door Weatherstrips
Storm Doors effectiveness Modern exterior doors, properly insulated, do not need storm doors....They do not add anything from an energy-savings point of view.
See: Storm Doors
Features like the strength of the door, its durability, maintenance requirements and energy efficiency should be taken into consideration…
See: Garage Doors Guide
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©2013 House-Energy, Help Homeowners reduce energy use and carbon emissions. Ed. Reisinh
